1. Field of the Invention
This invention relates generally to infant incubators and radiant warmers, and more specifically to an improved thermal barrier device for premature infants.
2. Description of the Prior Art
Maintenance of body temperature in premature infants is of critical importance to their health and survivability. Accordingly, specialized devices have been developed to help provide this thermal maintenance, such as open radiant warmer beds and convection-warmed infant incubators. Such devices offer an efficient means for re-warming premature infants who have been cold stressed, while allowing access to the infant for emergency resuscitation, diagnostic, and therapeutic procedures, and further enabling uninterrupted heat delivery for maintenance of body temperature during routine nursing and medical care.
However, there are some disadvantages in using these radiant warmer beds (and, to a lesser degree, infant incubators) for such purposes. For example, some premature infants cared for in these devices have exhibited large increases in insensible water loss, which significantly complicates the management of fluid and electrolyte therapy in the infant. Furthermore, some infants nursed under radiant warmers exhibit increased oxygen consumption, which suggests that they may be subject to significant thermal disturbances, and thus indicates a failure to achieve the desired thermoneutral state.
Some neonatal care practitioners have addressed these problems by covering the infants with a thin blanket of plastic wrap, bubble wrap, or other plastic film material. Such material acts as a shield to reduce insensible water loss to the infant, reduce convective air currents within the infant's thermal microenvironment, and reduce the radiant or convective heat input required to maintain the infant's body temperature. In addition, it has been determined that infant oxygen consumption is reduced as a result of the changes produced by such a blanket in the infant's thermal environment. See, for example, "Reduction of Oxygen Consumption, Insensible Water Loss, and Radiant Heat Demand with Use of a Plastic Blanket for Low-Birth-Weight Infants Under Radiant Warmers", by Stephen Baumgart, M.D., in Pediatrics, Volume 74 No. 6 (December 1984).
Unfortunately, use of these plastic film blankets has several practical disadvantages. For example, preparation and placement of these blankets is inefficient and time-consuming to the practitioner, generally requiring measuring, cutting, and taping of the plastic. Furthermore, even when in place, the plastic film material does not form an effective seal around the infant. In addition, these blankets are not easily cleaned, thereby requiring frequent replacement of the blankets to avoid contamination and/or infection to the infant. Also, some infants seem to find contact with the plastic to be irritating, and thus they may become aggravated by its presence. Other, simply active infants tend to push the blanket off of themselves, thereby negating the beneficial effects of the blanket in the first place. Still further, such blankets tend to be so thin and frail that they do nothing to provide an effect of sensory deprivation (e.g., quiet), something which is believed to be desirable in the neonatal care environment. Finally, while such blankets are generally optically transparent, they tend to distort a clear view of the infant.